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Mega A Level Maths Thread MK II Watch

1. (Original post by justinawe)
Hmm?

You understand that m at Q is ?

You understand this means that at Q is ?

You understand that ?

and thus ?
Ohhhhh..... OK... !

its just a revers - ie thing

I got it! /// Wow!! - Your maths skills are comparable to a DON!!

i would rep but im out
thank you!

ryan
2. (Original post by purplemind)
It would be really nice.
Attached Files
3. probability.doc (89.0 KB, 250 views)
4. (Original post by tigerz)
Thank you.
The attached document looks quite useful.
5. (Original post by purplemind)
Thank you.
The attached document looks quite useful.
Haha no problem
6. (Original post by tigerz)
Daymnn guuurl loving those colorful notes
7. (Original post by ryanb97)
Ohhhhh..... OK... !

its just a revers - ie thing

I got it! /// Wow!! - Your maths skills are comparable to a DON!!

i would rep but im out
thank you!

ryan
Oh come now, I'm just more experienced you're in year 10 or 11 iirc...
8. (Original post by tigerz)
Haha no problem
Anyway, I'm being a bit thick now, but seriosly, I don't know how to go about doing it.
I am given P(A)=3/4
P(B|A)=1/5
P(B'|A')=4/7
They want me to find P(A and B)- that's easy, I did it. But then they want P(B). And it confuses me a bit.
9. c2 friday aaaaarghhh
10. (Original post by Boy_wonder_95)
Daymnn guuurl loving those colorful notes
I didn't realise you were american
11. (Original post by purplemind)
They want me to find P(A and B)- that's easy, I did it. But then they want P(B). And it confuses me a bit.
Surely the ?

EDIT: I meant
12. (Original post by Scientific Eye)
Surely the ?
But why?
Even if they are not mutally exclusive?
13. (Original post by justinawe)
Oh come now, I'm just more experienced you're in year 10 or 11 iirc...
year 11 .... but i must say i havent been in a proper maths lesson in 4 years

and i wont be next year...

lol

ryan
14. (Original post by justinawe)
I didn't realise you were american
Haha, is that a bad thing?
15. (Original post by Boy_wonder_95)
Daymnn guuurl loving those colorful notes
(Original post by justinawe)
I didn't realise you were american
LOOL! IKR thank youuu, but I only just realised they have loads of spelling errors btw, we're literally meeting on every thread
16. (Original post by Boy_wonder_95)
Haha, is that a bad thing?
No, of course not. Are you really, though?
17. (Original post by justinawe)
No, of course not. Are you really, though?
Nah , it's just that TSR has 'colourful' underlined in red which buggers me
18. (Original post by purplemind)
But why?
We are only concerned with the outcomes where event occurs.

Look at the probability tree. You have event and event . We don't care if event happens or not, only that event does happen. Hence we find all the ends of the probability tree where event is an outcome and then add them up.

That is, if I'm not incorrect in my thinking.
19. (Original post by purplemind)
Anyway, I'm being a bit thick now, but seriosly, I don't know how to go about doing it.
I am given P(A)=3/4
P(B|A)=1/5
P(B'|A')=4/7
They want me to find P(A and B)- that's easy, I did it. But then they want P(B). And it confuses me a bit.
Use these two formulae (which are in the formulae booklet):

Find using the first formula, then sub it into the second one.
20. (Original post by tigerz)
LOOL! IKR, but I only just realised they have loads of spelling errors btw, we're literally meeting on every thread
Still they make my S1 notes look rusty in comparison , who me or justin?
21. (Original post by Scientific Eye)
We are only concerned with the outcomes where event occurs.

Look at the probability tree. You have event and event . We don't care if event happens or not, only that event does happen. Hence we find all the ends of the probability tree where event is an outcome and then add them up.

That is, if I'm not incorrect in my thinking.
Ok, so P(B|A)=1/5
P(B|A')=3/7
I add them and get P(B)=22/35
My textbook says it should be 9/35
So I don't know if it is right and the answer in the textbook is wrong or the other way round.

(Original post by justinawe)
Use these to formulae (which are in the formulae booklet):

Find using the first formula, then sub it into the second one.
I still don't know how to find P(A U B) from what I am given. :<

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